I was looking on this website for an Alm build but I notice a little gold shield. When I clicked it it just showed me a list of gold support characters. Can anyone explain this to me? Thanks in advance.
It's exactly what it sounds like. All of these units have the ability and potential to support their teammates. Units with large HP pools and self-healing skills like Lucina can run medic builds with Reciprocal Aid/Ardent Sacrifice, dancers like Lene can grant an extra turn to an ally, buff bots like B!Lucina and Marth can provide valuable combat buffs, debuffers like Arvis can simultaneously debuff multiple stats, etc.
in alm's case he has a weapon refine that buffs teammates plus restores his hp every other turn - pop a hp giving support skill, renewal b and a buff c & seal and you have a dragonkilling fast sword unit that can help team and heal (though same goes for almost any falchion unit). there are better uses for his refine options or team buffers in general though.
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